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Diffstat (limited to 'src/mame/drivers/mits680b.cpp')
-rw-r--r-- | src/mame/drivers/mits680b.cpp | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/src/mame/drivers/mits680b.cpp b/src/mame/drivers/mits680b.cpp new file mode 100644 index 00000000000..f0f0d24ed15 --- /dev/null +++ b/src/mame/drivers/mits680b.cpp @@ -0,0 +1,117 @@ +// license:BSD-3-Clause +// copyright-holders:Miodrag Milanovic, Robbbert +/*************************************************************************** + + MITS Altair 680b + + 03/12/2009 Skeleton driver. + + 08/June/2011 connected to a terminal + +Monitor Commands: +J +L switch to terminal mode +M +N modify memory in a limited way +P this does a rti and causes a momentary crash. Weird. + + +ToDo: +- Hook ACIA back up, when there is some way to use it. + + +****************************************************************************/ + +#include "emu.h" +#include "cpu/m6800/m6800.h" +#include "machine/mos6551.h" +#include "machine/terminal.h" + +#define TERMINAL_TAG "terminal" + +class mits680b_state : public driver_device +{ +public: + mits680b_state(const machine_config &mconfig, device_type type, const char *tag) + : driver_device(mconfig, type, tag), + m_maincpu(*this, "maincpu"), + m_terminal(*this, TERMINAL_TAG) + { + } + + required_device<cpu_device> m_maincpu; + required_device<generic_terminal_device> m_terminal; + DECLARE_READ8_MEMBER(terminal_status_r); + DECLARE_READ8_MEMBER(terminal_r); + DECLARE_READ8_MEMBER(status_check_r); + DECLARE_WRITE8_MEMBER(kbd_put); + UINT8 m_term_data; + virtual void machine_reset(); +}; + +READ8_MEMBER( mits680b_state::status_check_r ) +{ + return 0; // crashes at start if bit 7 high +} + +READ8_MEMBER( mits680b_state::terminal_status_r ) +{ + return (m_term_data) ? 3 : 2; +} + +READ8_MEMBER( mits680b_state::terminal_r ) +{ + UINT8 ret = m_term_data; + m_term_data = 0; + return ret; +} + + +static ADDRESS_MAP_START(mits680b_mem, AS_PROGRAM, 8, mits680b_state) + ADDRESS_MAP_UNMAP_HIGH + AM_RANGE( 0x0000, 0x03ff ) AM_RAM // 1024 bytes RAM + //AM_RANGE( 0xf000, 0xf003 ) AM_DEVREADWRITE("acia", mos6551_device, read, write ) + AM_RANGE( 0xf000, 0xf000 ) AM_READ(terminal_status_r) + AM_RANGE( 0xf001, 0xf001 ) AM_READ(terminal_r) AM_DEVWRITE(TERMINAL_TAG, generic_terminal_device, write) + AM_RANGE( 0xf002, 0xf002 ) AM_READ(status_check_r) + AM_RANGE( 0xff00, 0xffff ) AM_ROM +ADDRESS_MAP_END + +/* Input ports */ +static INPUT_PORTS_START( mits680b ) +INPUT_PORTS_END + + +void mits680b_state::machine_reset() +{ + m_term_data = 0; +} + +WRITE8_MEMBER( mits680b_state::kbd_put ) +{ + m_term_data = data; +} + +static MACHINE_CONFIG_START( mits680b, mits680b_state ) + /* basic machine hardware */ + MCFG_CPU_ADD("maincpu",M6800, XTAL_1MHz / 2) + MCFG_CPU_PROGRAM_MAP(mits680b_mem) + + /* video hardware */ + MCFG_DEVICE_ADD(TERMINAL_TAG, GENERIC_TERMINAL, 0) + MCFG_GENERIC_TERMINAL_KEYBOARD_CB(WRITE8(mits680b_state, kbd_put)) + + /* acia */ + //MCFG_ACIA6551_ADD("acia") +MACHINE_CONFIG_END + +/* ROM definition */ +ROM_START( mits680b ) + ROM_REGION( 0x10000, "maincpu", ROMREGION_ERASEFF ) + ROM_LOAD( "mits680b.bin", 0xff00, 0x0100, CRC(397e717f) SHA1(257d3eb1343b8611dc05455aeed33615d581f29c)) +ROM_END + +/* Driver */ + +/* YEAR NAME PARENT COMPAT MACHINE INPUT INIT COMPANY FULLNAME FLAGS */ +COMP( 1976, mits680b, 0, 0, mits680b, mits680b, driver_device, 0, "MITS", "Altair 680b", MACHINE_NOT_WORKING | MACHINE_NO_SOUND) |